Department A had 5,000 units in work in process that were 77% completed as to labor and overhead at the beginning of the period, 30,200 units of direct materials were added during the period, 33,100 units were completed during the period; and 2,100 units were 34% completed as to labor and overhead at the end of the period. All materials are added at the beginning of the process. The first-in, first-out method is used to cost inventories. The number of equivalent units of production for material costs for the period was a. 33,100 b. 28,100 c. 35,200 d. 30,200